ATSC 3.0 is an Internet Protocol (IP)-based broadcasting standard that provides end-to-end delivery of IP-based content. ATSC 3.0 allows service providers to provide protected, as well as unprotected, content. In such systems, for the protected content, an efficient mechanism for the delivery and reception of rights (e.g., DRM-related information) to access such content is needed.
Broadcast television receivers, by their nature, receive a signal from whichever broadcast signal the user has chosen based on the service the user has selected. Broadcast signals often carry a plurality of services in their digital multiplex. In ATSC 1.0 these services are called “virtual channels,” whereas ATSC 3.0 refers to them as “services”.
An ATSC Service is a collection of media components and/or metadata delivered to receivers in aggregate. Components may be of multiple media types. A service may be either continuous or intermittent. A service can be real time or non-real time, and real time services can include a sequence of TV programs.
In ATSC 3.0, a service can be an application that may or may not have live broadcast streaming audio/video content. A service may also include non-real-time content such as video-on-demand, or other interactive content like one might find on a web page. Also, some or all components of an ATSC 3.0 service may be delivered via the broadband (interpret) path. A service that includes components from both broadcast and broadband is called a “hybrid” service.
An EMM typically provides access to one or more services, for a limited period, typically one month, by means of the decryption keys necessary to decrypt the content it contains. Each EMM targets an individual receiver; the information contained within it is cryptographically tied to secure information contained within the target receiver. If a receiver can access the EMM that grants access to a service, such access will continue for a period of time even if no further EMMs are found. Like a magazine subscription, if the subscription period comes to an end for an access-controlled service and no renewal is forthcoming, the receiver's access to that service terminates. The expiration feature ensures that a user cannot continue to receive access simply by blocking reception of EMMs. An EMM may itself revoke access; in that case reception of the EMM would result in the receiver terminating access to the associated service or services.